What this SHA-512 generator does
This tool computes the SHA-512 cryptographic hash of any text you enter, returning a fixed 512-bit value as 128 hexadecimal characters. SHA-512 is used for file integrity, certificate signing, and as the basis for HMAC-SHA512 and the SHA-512/256 truncated variant.
How it works
SHA-512 is defined in NIST FIPS 180-4. The UTF-8 bytes of your text are padded so the length is congruent to 896 modulo 1024 bits, with the original 128-bit length appended. The message is processed in 1024-bit blocks through 80 rounds of compression over eight 64-bit working variables, using constants derived from the fractional parts of the cube roots of the first 80 primes. This tool uses the browser’s native crypto.subtle.digest("SHA-512", data), so output matches the standard exactly.
Tips and notes
- Operating on 64-bit words, SHA-512 is often faster than SHA-256 on modern 64-bit CPUs.
- A single changed character produces an entirely different digest (avalanche effect).
- Example: the empty string hashes to
cf83e1357eefb8bdf1542850d66d8007d620e4050b5715dc83f4a921d36ce9ce47d0d13c5d85f2b0ff8318d2877eec2f63b931bd47417a81a538327af927da3e. - For passwords, prefer a salted slow KDF (Argon2, bcrypt, scrypt) rather than a single SHA-512 pass.